Abstract: Most scientific research on a “degrowth-economy” is motivated by finding pathways to build a just society, in terms of both intragenerational justice and intergenerational justice. As conflicts in attaining the two justices (may) arise in the design and implementation of sustainability policy, the relationship between the objectives of intragenerational and intergenerational justice (‘justice-relationship’) has to be considered carefully. In this paper, we aim for a systematic investigation of the ‘justice-relationship’ against the backdrop of given societal circumstances, focusing on environmental justice – that is, justice in the distribution of access rights to ecosystem services. With an ecological-economic model, we simulate how different assignments of resource utilization rights to potential ecosystem users impact on the justice-relationship depending on system determinants. These system determinants include population development, substitutability of ecosystem services, technological progress and political restrictions on redistribution. Therewith, the model provides a tool to systematically analyze the interdependencies between the objectives of intragenerational and intergenerational justice in ecosystem use.